Pacquiao purse, boy I took another belt
In boxing, a “purse” refers to the payout scheme to the boxers which includes sources of income from: PPV sales, live ticket sales, and a guaranteed sum from the promotor(s) and venue of the fight. “Pacquiao purse” refers to the purse / amount of money that world-class boxer Manny Pacquiao recieves from his bouts. Ross claims to have a comparable amount (I mean, he named his mixtape Rich Forever).
He continues to to use this boxing theme to say he took (bought) another belt (probably something luxury like Louie Vatton), while still referencing the amount of championship title belts that Manny Pacquiao has.
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